Liquid fuel vaporizer



Sept. 19, 1950 w. A. CLEMEQENTS 2,

LIQUID FUEL VAPORIZER 1 1 Filed Juhe' 1, 1946 INVENTORC W-A.CZemen2s BY mm Patented Sept. 19, 1950 omcs *LIQU-ID" FUEL V'APORIZER William A; Clements, GlendalefC alif. --Aiipliclation June 1, 1946, Serial Nofi673fi8 "'20" Claims. (01. 48- 1 07) [1 The pres'ent invention relates generally to vaporization of liquid" hydrocarbons and more particularly tomeans' for controlling such vaporization to the end that more accurate burner control may be obtained.

vaporizationof 'liquid' hydrocarbon is of great I importance in' various industries for supplying gaseous fuelito industrial furnaces and ovens and may be found indispensable in places where the supply: of natural or commercial gas is-either insufficient, hon-unif orm ,1 or both.

rThe-i principal object of 1 this invention is to provide a vaporizing system of this character which will operate over a' considerable range to supply the-amount of heat required to maintain a number of burners in operation and which will, ;under--a11 operating" conditions, produce a combustible mixture ofuniform predetermined character or quality.

Other objects and the many advantageous feartures of the invention will be'apparent' from the following detailedfldescription and by referring to the accompanying drawings wherein:

i Figcl'is'a general'view'of a fuel vaporizing'sys- :tem embodying the invention;

Fig. '2 is'a plan view, partly insection, of the 3 generator of the system shown in Fig;- 1;

Fig.3 is-a' cross-sectional view'of a modified form of generatoruse'd' in the system shown in Fig. 1;"and

Fig. 4 lea-sectional detail-view, on a larger scale, of certain parts of the-generator of Fig.3, the importance of which ishereinafter fully explained.

The-structure of the invention, in the form illustratedfis designed to supplygaseous fuel to a 'battery of burners (not-shown) through a manifold I. "A non 'pulsating flow of air from a IOWFGT'OGhEI equivalent sourceis supplied to the manifold through a'pipe 2,'terminating ina contracted 'oriflce or nozzles. The' latter is seated withina casing 4,-having a contracted passage 5 in axial ali nment with said nozzle, and it is noticedithat the area of the'passage continuing -through therpo'rtionof the casing extending to and conneotin'gwith the manifold -I gradually increases, thereby'toform a Venturitub'e eat this point.

'A' vaipor generator *Sis shown placed below the '"casing band'it communicates therewith through a pipe' connection "I. The =generator comprises a substantially oval casing, circular in horizontal cross section. The-casingis;by alplate fmdi'vid- =ed-into an upper *vaporizing chamber and a lower combustion-chamber I2. It is furthermore importantto note that 'the central portion of the plate H) is recessed-to formadome ll] rising into the upper chamber.

In the bottom 'of the TgGIIGI'atOI is seated a burner block l3. A pipe line" M'is cut into the manifold -I at? l5,"and' it extends to a position directlybelowthe "burner block, at which point it is fitted with'a burnernozzle It.

In order to put the system into operation, it is first required to heat the generator casing, and

.this mayhedone-byddirecting raw gas past a valve l'linto'the'lower; horizontal portion of the pipe-line I 4; substantially asshown, and to ignite this gas at the nozzle 16.

The'=air':'supply"to"the"'casing 4, which con- "veniently may be termedthe mixing head of the system -is atthe same"tin'1'er turned on, and the air rushing'into'the 'manifold creates and maintains' a 'stateof compression therein.

'Thei-flamefroimthe burner nozzle It rises through the"'bt.irner block I3 into the dome Hi and'around'thisbliick into the lower, combustion chamber I2. It is n'o'w noticed that a series of tubularmembersflfl are vertically seated in the plate lfland 'that "theyextend nearly to the top a'ndbottom of the generator casing. It is importanttomotathatthe'flanie or heat descending' into'the'lower chamber, in the manner'just described, rises thitough these members to pass through the-Pupper 'cha'mber it around the dome m and-through the' pipetonnection 1 into the mixing head 4.

Liquid fuel' from'a convenient source of supply is'admitted 'through apipe '22 to a float chamber zilra when,aftefiafshoi'tperiod of time, the generator has been sufli'ciently heated for vaporization purposes. Thefuelifiowsthrough a pipe connection" Minto the'generator and through the middle section -iplate510,' 0ver''the top of 'whichit "spreads to" formr 't-hero'n "a? pool, the surface level of which" is controlled'from the float chamber 2 3.

'Becausethe' plate [0 1 and the dome ic become intensely' heate'd, it' is found"that a portion of the liquid fuel of-thepool becomesvaporized and is 4.5 :dra-wnwup"throughfithe mixing 'head 4 and, in-

termixed with airst'hrough the-manifold to the burners.

Duringthis initial'firin'g;operation, when the air :flow-E through "the pipe 2 starts, it has been found thatna portion of. the air? under pressure within thermanifold commentesto'fiow through thezpipelinafl @to the burner [Band that the air passing through the mixing head becomes more and more *saturated with fuel vapor from-the generator. 'fis soon as the' properratio of vaporized fuel to air has been reached, it is found that the intense heat of this mixture will be sufficient to maintain combustion within the generator sufficiently for vaporizing purposes and so to make it possible to turn off the raw gas supply. The system now functions entirely on air and vapor mixture and the amount of heat developed and the rate of flow of vaporized fuel passing through the manifold to the burners is in proper proportion to the flow of air through the mixing head.

It is customary in practice to regulate the air flow through the pipe 2 manually or by remote temperature control, and the system will continue automatically to supply a required flow of uni formly mixed air and vaporized fuel through the manifold. And as this mixed air and vapor flow is accelerated, it tends to increas the pressure within the manifold, thereby to increase the fiow of pre-mixed fuel passing to and through the generator burner, 'in turn correspondingly increasing the rate of fuel vaporization within the generator.

As the fuel vaporization rat increases or decreases, it is found that the liquid level controller within the float chamber correspondingly varies the liquid fuel supply to the generator, thereby to maintain a substantially uniform volume of fuel within the. generator at the same liquid level.

From the foregoing description, it is seen that the generator becomes quickly sufflciently preheated by the flame of the burner l6 to vaporize fuel on the middle section plate Ill. But it is important to note that the flame, or the superheated gases rising from the flame do not pass directly through the liquid fuel as in other systems that have come to my notice, but flow through the tubular members into the upper chamber of the generator, above the liquid fuel surface. Also that, in passing through this upper chamber, the rising vapor becomes more intensely heated and more completely vaporized by contact with the surface of thedome l0. In order further to induce complete vaporization, I have shown the members 29 closed at the top and made with orifices or jetslS laterally directed from one side of the members, thereby to produce a whirling movement of the combining vaporized material within the chamber, thus preventing heavy oil vapor from passing in to pipe 1 until completely vaporized and super-heated.

In the manifold, below the point I5, may be placed a condensate trap 27, and a ipe-line 28 extends from this trap to the fuel supply pipe 24. It is noticed that the pipe-line 28 is shaped to form a U-seal which, when it becomes filled with condensate or liquid fuel, preventsreturn of airgas mixture from the manifold to the generator. Once the system is in full operation, this condensate return system may remain dormant, but when first starting and all piping and the manifold are cold, it is generally necessary to provide such condensate return. As a safety relief in the event of excess pressure within the generator, I prefer to out a conventional type of poppet relief valve 30 into the upper chamber of the generator. A butterfly valve 33 is cut into the pipe connection above the valve 3| to control the flow to the mixing head 4 and thereby to provide additional means for regulating the flow of vaporized fuel mixture or gaseous fuel to the manifold.

One difliculty in connection with the use of liquid hydrocarbon fuel in any device as ordinarily found in commercial use, is that such high degree of heat is required to heat the fuel sufiiciently to cause evaporation thereof that carbon lower temperature of the liquid fuel within the pool is maintained and vaporation thereof is effected by sweeping the combustion products along the surface of the pool before they rise into themixing head 4.

Where heavy hydrocarbon fuel is used the danger of formation of carbon deposits is even greater, and. it may for this reason in such cases be preferable to substitute the type of generator illustrated in Figs. 3 and 4.

The generator casing 40 may in this case remain substantially as abov described, and the middle section plate M is shown fitted with a dome 52 which also may remain substantially unchanged, although it is shown somewhat smaller in diameter in order to afford additional space for the circulation of the combustion products around the dome.

It is noticed that in this case the tubular members 20 have been modified to show a series of short pipes 43 extending through the plate 4| and bent at right angles above this plate or, for convenient manufacture, fitted with an elbow 44 in which a screw plug is seated. A nozzle 46 extends through the elbow into the passage through the screw plug, and it is noticed that this passage is shaped to form a venturi designed to increase the velocity of the vapors drawn through the nozzle from the surface of the pool which is formed on top of the plate 4|. In order to expedite and increase the flow through the nozzle, it is shown made with a downwardly directed portion 4'! terminating close to the surface of the liquid in the pool.

vith the generator constructed in this manner, it is seen that the superheated combustion products rising through the pipes 43 effectively complete the gasification of the vapors drawn from the surface of the pool, and that for this reason it is not necessary to heat the plate 4| to as high a degree as in the case of the above described generator, and that for this reason all danger of carbon formation is substantially eliminated. It is, however, desirable to make certain that the plate ll becomes evenly heated over the entire surfac thereof, and it is for this reason advisable to mount a flange 48 on the top edge of the burner l3 to extend parallel with the plate 4! nearly to the side wall of the generator casing, substantially as indicated in Fig. 3. With the introduction of this flange it is seen that the flaming combustion products rising from the burner are forced to travel along the under surface of the plate 4| and through the narrow annular space 49 between the flange and the generator casing before reaching the entrance to the pipes 43.

It is possible, should it be so desired, to cut off the generator from the mixing head and to proportionally mix a gaseous fuel with the air passing through the head. Illustrative of such combination, I have shown a conventional 3-way valve 3| cut into the pipe connection I, and a supply pipe 32 carries gaseous fuel through this valve to the mixing head when the generator is cut off therefrom.

It will be apparent from the foregoing detailed description that I have provided a very complete and highly efficient hydrocarbon vaporizing and.

air mixing device for delivering vaporized fuel mixture of uniform quality under all operating conditions to industrial furnaces; I do not, how ever, limit myself to; the specific details and arrangements shown and described, the invention beinglimited only by the scope of theolaims-here 7 to appended.

I claim:

1. A liquid fuel vaporizing device including a generator having anoutlet at the top and divided by" a center partition into an upper and lower chamber, said partition being centrally recessedto form a dome rising therefrom into. said upper chamber thereby to form areservoir for liquid fuel on top of said partition, aburner below: the generator, a fuel; supply line tosai'd burner, a passage directing: the flame from the burner againstxthe. underside of said domeand down into the space below said central partition, passages for carrying combustion products from this combustion space into. the: chamber above said reservoir, means carrying liquid fuel: through: the lower chamber of the;- generator: to. the reservoir, and means associated therewith for controlling the; liquid level within the: reservoir,

2., A liquid fuel vaporizing device. including, agenerator having an, outlet at the top, said enerator being divided into an upper and a lower chamber, a burner below the generator for heating said lower chamber; afuel line to said burner,

a pipe for carrying liquid fuel through the heated lower chamber intothe upper chamber inform a reservoir at thebottom thereof, passagesfor the combustion products from, the. lower chamber to the space above said liquid reservoir, and means, for controlling the. liquid level within the reservoir.

3;, A liquid fuel vaporizing device including a generator, a plate centrally dividing said generator into an upper and a lower chamber, said plate being recessed to form a dome rising intosaid upper chamber, there being. a. reservoir formed on said plate about said dome, a series. of tubular members vertically seated in said plate and extending substantially through, the two chambers, a burner below the generator, a fuel supply line to said burner, a passagefor directing the flame from said burner againsttheunderside of saiddome and down into said lower chamber then through the said tubular members. to F there being formed a reservoir for liquid fuel on said member about said dome, pipes vertically seated in said central member and extending nearly to the top and. bottom of the generator, said pipes being closed at the. top. and having outlets near thetop on one side thereof, a burner below thegenerator, a fuel line to. said burner, a passage for directing the flame fromsaid burner against the underside of said dome down into the lower chamber of the generator, the combustion products passing through said. pipes and the lateral outlets at the top thereof into. said upper chamber and out through, said top opene ing, the combustion. products in. passing through the side openings of said pipes being given a whirlingmovement: about said dome above said reservoir before passing out of said outlet.

5: A liquid fuel vaporizing device including a generator, a member centrally: dividing said generator intoan upper and a lower chamber, said upper chamber having an outlet at the top, said member being recessed to form a dome rising into said upper chamber nearly to the top thereof, there being formed a reservoir for liquid fuel on said member about said dome, pipes vertically seated in said central member and extending nearly to the top and bottom of the generator, said pipes being closed at the top and having outlets near the top on one side thereof, a burner below the generator, a fuel line .to'said burner, a passage for directing the flame from said burner against the underside of said dome down into the lower chamber of the generator, the combustion products-passing through said pipes into said upper chamber and out through said top opening, the combustion products in passing through the side openings of said pipes being given a whirling movement about said dome above said reservoir before passing out of said outlet, means carrying liquid fuel through said heated lower chamber into said reservoir, and means for controlling the liquid level therein.

6. A liquid fuel vaporizing device including a generator having an outlet at the top, said generator being divided into an upper and a lower chamber, a burner below the generator for heating said lower chamber, a fuel'line to said burner, a pipe for carrying liquid fuel through the heated lower chamber into the upper chamber to form a reservoir at the bottom thereof, passages for the combustion products from the lower chamber tothe space above said liquid reservoir, means controlling the liquid level within the reservoir, and a relief valve in said upper chamber.

'7. A liquid fuel vaporizing device including a generator having an outlet at the top, said generator being divided into an upper and lower chamber, a burner below the generator for heating said lower chamber, a fuel line to said burner, a pipe for carrying liquid fuel through the heated lower chamber into the upper chamber to form a reservoir at the bottom thereof, passages for the combustion products from the lower chamber to the space above said liquid reservoir, said passages being bent at the top to discharge the combustion products along the surface of the liquid in the reservoir, and a nozzle extending into said bent portion of each passage, each nozzle having a downwardly directed portion outside of the passage and extending nearly to the surface of the liquid within said reservoir.

8.,I n a liquid fuel vaporizing device in c0mbination, a generator divided into an upper vaporizing chamber having a liquid fuel reservoir therein and a lower combustion chamber, a conduit for air under. pressure, pipe connection from said upper chamber to said conduit, a burner for heating, said combustion. chamber, a fuel supply line to said burner, passages for the combustion products through the space above said reservoir to the said pipe connection, and a conduit leading, from a point in said air conduit in front of said pipe connection to said burner.

9.,In a liquid. fuel vaporizing device in combination, a generator divided into an upper vaporizing chamber having a liquid fuel reservoir therein and a lower combustion chamber, a conduit for. air under pressure, pipe connection from saidupper. chamber. to said air, conduit, a burner for heating said combustion chamber, a fuel supply line to said burner, passages for the combustion products through the space above said reservoir to the said pipe connection, a conduit leading from a point in said air conduit in front of said pipe connection to said burner, a pipe carrying liquid fuel through the combustion chamber to said reservoir, and means associated with said pipe for controlling the liquid level within the reservoir.

10. In a liquid fuel vaporizing device in combination, a generator divided into an upper vapor: izing chamber having a liquid fuel reservoir therein and a lower combustion chamber, a mixing chamber, a pipe carrying air under pressure to said chamber, a'pipe connection from said upper chamber to said mixing chamber, a mixed fuel conduit extending from said mixing chamber in axial alignment with said air pipe, a burner for heating said combustion chamber, a fuel supply line to said burner, passages for the combustion products from said combustion chamber through the space above said reservoir to the said pipe connection, a pipe carrying liquid fuel through the combustion chamber to the reservoir, and means associated with said pipe for controlling the liquid level within the reservoir.

11. In a device for supplying vaporized fuel to a battery of furnaces, a manifold leading to said furnaces, a pipe carrying air under pressure to said manifold, a mixing chamber encompassing the adjoining ends of said pipe and manifold, a generator divided into an upper vaporizing chamber having a liquid fuel reservoir therein and a lower combustion chamber, pipe connections from said upper chamber to the manifold, a burner below the generator for heating the combustion chamber, passages for the combustion products from the combustion chamber through said upper chamber and the said pipe connection to the mixing chamber, a conduit for carrying liquid fuel through the combustion chamber into said reservoir, and means associated with said conduit for controlling the liquid level within the reservoir.

12. In a liquid fuel vaporizing device in combination, a generator horizontally divided into an upper vaporizing chamber having a liquid fuel reservoir therein and a lower combustion chamber, a conduit for, air under pressure, a pipe connection from said upper chamber to said conduit, a burner below the generator for heating said combustion chamber, conduits for carrying the combustion products from the combustion chamber through the space above said reservoir to the pipe connection, a pipe carrying gaseous fuel to said pipe connection, and a valve controlling flow of fuel from the upper chamber or from said gaseous fuel pipe to said air conduit.

13. In a liquid fuel vaporizing device in combination, a generator divided by a horizontal partition into an upper vaporizing chamber and a lower combustion chamber, the center portion of said partition being recessed to form a dome rising into said upper chamber and providing a reservoir about said dome, a conduit for air under pressure, a pipe connection from said upper chamber to said conduit, a burner for heating the combustion chamber, passages for the combustion products from said chamber through the space above said reservoir to the said pipe connection, a conduit from said compressed air conduit to said burner, a pipe carrying liquid fuel through the combustion chamber to the reservoir, and a pipe from the compressed air conduit to said liquid carrying pipe for returning 8. l condensed fuel from the compressed air conduit, said condensate pipe being U-shaped at the bottom to form therein a liquid seal.

.. 14. In a liquidfuel vaporizing device in combination, a generator divided into an upper vaporizing chamber having a reservoir therein and a lower combustion chamber, a conduit for air under pressure, pipe connection from said upper chamber to said conduit, a butterfly valve in the pipe connection,a burner below the generator for heating said combustion chamber, passages for the combustion products through the space above said reservoir to the said pipe connection, and a conduit from said compressed air conduits to the burner.

15. In a liquid fuel vaporizing device in combination, a generator divided into an upper vaporizing chamber having a reservoir therein and a lower combustion chamber, a conduit for air under pressure, pipe connection from said vaporizing chamber to said conduit, a butterfly valve in said pipe connection, a burner below the generator for heating the combustion chamber, passages for the combustion products through the space above said reservoir to the pipe connection, a conduit from said compressed air conduit to the burner, a pipe carrying liquid fuel through the combustion chamber to the reservoir, and means associated with said liquid fuel pipe for controlling the liquid level within the reservoir.

16. In a liquid fuel vaporizing device in combination, a generator divided into an upper vaporizing chamber having a fuel reservoir therein and a lower combustion chamber, a conduit for air under pressure, pipe connection from the vaporizing chamber to said conduit, a burner below the generator for heating the combustion chamber, and conduits from the combustion chamber to the space above the reservoir for carrying the combustion products across the surface of the liquid within the reservoir to said pipe connection. 7

17. In a liquid fuel vaporizing device in combination, a generator divided into an upper vapor- 12mg chamber having a liquid fuel reservoir therein and a lower combustion chamber, a conduit for air under pressure, pipe connection from said vaporizing chamber to said conduit, a burner below the generator for heating the said combustion chamber, passages from the latter to the space within the vaporizing chamber above said reservoir, said passages terminating at the top in lateral outlets for carrying the combustion products along the surface of the liquid fuel within the reservoir to said pipe connection, nozzles in said outlets drawing vaporized fuel from above the surface of the liquid Within the reservoir, and an annular baffle plate extending horizontally into the space within the combustion chamber from said burner, the lower ends of said passages being seated in and extending through said plate.

18. A liquid fuel vaporizing device including a generator divided by a horizontal partition into an upper vaporizing chamber and a lower combustion chamber, a burner rising into said combustion chamber, said burner having an annular bafiie plate extending from the top thereof parallelwith said partition, means carrying liquid fuel through the combustion chamber and the partition to form a pool on topthereof within the vaporizing chamber, and passages for the combustion' pro uctsrisin'g through the bafiie plate andthe partition, said passages terminating at the top in laterally directed nozzles.

19. A liquid fuel vaporizing device including a generator divided by a horizontal partition into an upper vaporizing chamber and a, lower combustion chamber, the center of said partition being recessed to form adome rising into the upper chamber, a burner rising into said combustion chamber, said burner having an annular baflie plate extending from the top thereof parallel with said partition, means carrying liquid fuel through the combustion chamber and the partition into the vaporizing chamber to form a pool about said dome on top of the partition, conduits rising through the baffle, plate and the partition, said conduits having lateral outlets at the top and nozzles seated in said outlets, said nozzles having downwardly directed portions forming inlets directly above the surface of the pool.

20. A liquid fuel vaporizing device including a generator divided by a horizontal partition in the upper vaporizing chamber and a lower combustion chamber, the center of said partition being recessed to form a dome rising into the upper chamber, a burner rising into the combusform a pool therein, conduits rising through the bafile plate and the partition, said conduits having lateral outlets at the top thereof, annular plugs seated in said outlets for axial adjustment therein, and nozzles seated in said outlets and extending into said plugs, the nozzles having downwardly directed portions forming inlets directly above the surface of the pool.

WILLIAM A. CLEMEN'I'YS.

REFERENCES CITED The following references are of record in the I file of this patent:

UNITED STATES PATENTS- Number Name Date 833,780 Eisenhuth Oct. 3, 1906 866,525 Seeley et a1 Sept. 17, 1907 906,276 I Peregrine Dec. 8, 1908 Reichhelm Mar. 16, 1926 

